(Invited, Digital Presentation) High-κ Gate Oxide Integration and Ohmic Contact Development for AlGaN/GaN MISHEMTs

Abstract

In this work we review our latest results concerning the integration of different high-κ dielectrics e.g. Al2O3, GdScO3 and TiO2 for gate passivation and the related development of ohmic contacts in metal insulator semiconductor high electron mobility transistor. Depending on deposition and crystallization temperature of the dielectric, a high-κ first and high-κ last process was used. For both concepts, the development of suitable ohmic contacts with low formation temperature were carried out. Vanadium based contacts for high-κ first and Au-free contacts for the high-κ last approach was shown. The influence of the ohmic contact formation temperature on the performance of the MISHEMT devices were studied for all high-κ gate passivation layer.